A tire deflector (a spat) described in Patent Document 1 shown below is arranged outside an engine undercover in a vehicle width direction. Concretely, an inclined surface is formed on the engine undercover at an outer end portion thereof in the vehicle width direction, and the tire deflector is arranged behind this inclined surface with respect to a vehicle and outside this inclined surface in the vehicle width direction. Then, when the vehicle travels, a traveling wind flowing outside the engine undercover in the vehicle width direction hits the inclined surface and the tire deflector. Therefore, the entire traveling wind is restrained from hitting the tire deflector. Thus, a Cd value (an air resistance coefficient) of the vehicle is restrained from deteriorating.